JP5110316B2 - Process for producing aromatic hydrocarbons and liquefied petroleum gas from hydrocarbon mixtures - Google Patents

Abstract

Disclosed is a process of preparing aromatic hydrocarbons and liquefied petroleum gas (LPG) from a hydrocarbon mixture, in which a non-aromatic compound in the hydrocarbon feedstock mixture is converted into a gaseous material having a large amount of LPG through hydrocracking, and an aromatic compound therein is converted into an oil component having large amounts of benzene, toluene, and xylene (BTX) through dealkylation and transalkylation, in the presence of a catalyst obtained by supporting platinum/bismuth onto a mixture support having zeolite and an inorganic binder. The gaseous product is separated into LPG and a mixture of methane and ethane depending on differences in boiling point through distillation, while the liquid product is separated into benzene, toluene, xylene, and C9+ aromatic compounds depending on differences in boiling point through distillation.

Description

  The present invention relates generally to a process for producing aromatic hydrocarbons and liquefied petroleum gas (LPG) from a hydrocarbon mixture. More specifically, the present invention relates to LPG (liquefied petroleum gas) by hydrocracking a non-aromatic compound in a hydrocarbon feedstock mixture in the presence of a platinum / bismuth supported zeolitic catalyst. And a process for converting an aromatic compound therein to an oil component containing benzene, toluene, xylene and the like by dealkylation and / or transalkylation reaction.

In general, aromatic hydrocarbons are produced by catalytic reforming (reformate) produced by a catalytic reforming process.
And pyrolysis gasoline produced by the naphtha cracking process
It is obtained by separating a feedstock oil rich in aromatic compounds from non-aromatic hydrocarbons by a solvent extraction process.
The aromatic hydrocarbon mixture thus separated is usually separated into benzene, toluene, xylene and aromatic compounds having 9 or more carbon atoms by the difference in boiling point, and used as a basic substance in the petrochemical industry. On the other hand, non-aromatic hydrocarbons are used as a raw material or fuel in the naphtha cracking process.

In this regard, U.S. Pat. No. 4,058,454 discloses a solvent extraction process for separating and recovering polar hydrocarbons from a hydrocarbon mixture comprising polar and nonpolar hydrocarbons. . The solvent extraction process known to those skilled in the art, including the patents, uses the property that aromatic hydrocarbons are generally polar. That is, when a solvent capable of dissolving polar substances, such as sulfolane, is contacted with a hydrocarbon mixture, polar aromatic hydrocarbons are selectively dissolved, and thus from non-polar non-aromatic hydrocarbons. To be separated. While the method has the advantage that a high purity aromatic hydrocarbon mixture can be obtained, it requires additional solvent extraction equipment and has the disadvantage of having to continuously supply solvent throughout the process. is there. Therefore, there has been a demand for a method for separating and obtaining aromatic hydrocarbons and non-aromatic hydrocarbons from the raw material oil without including an additional solvent extraction step.

Efforts have been made to utilize reaction systems other than solvent extraction to separate aromatic compounds from non-aromatic compounds. Non-aromatic compounds mixed with aromatic compounds are converted to gas phase hydrocarbons by hydrocracking reaction in the presence of a catalyst, and aromatic and non-aromatic mixtures are located downstream of the reactor They are separated from each other using a gas-liquid separator. Such a concept was developed in US Pat. No. 3,729,409. In addition, U.S. Pat. No. 3,729,409, U.S. Pat. No. 2,849,290 and U.S. Pat. No. 3,950,241 describe a linear hydrocarbon component mixed with an aromatic compound. The object is to produce a high-quality gasoline component by increasing the aromatic content in the liquid phase component by hydrocracking ZSM-5 type zeolite to convert it into a gas phase component. Such a concept is disclosed in U.S. Pat. No. 5,865,986, in which a benzene / toluene mixture is formed by a reforming process in which a part of a continuous reactor of the reforming process is filled with a zeolite-based catalyst. Created for increased production. Further, US Pat. No. 6,001,241 discloses a method for increasing the yield of aromatic components by charging a part of the reactor in the reforming step with a zeolite-based catalyst having similar reaction characteristics. Is disclosed. However, the concept is not used as a separate process from the modification process for the production of aromatic components. When processing feedstock oil including reformed oil and pyrolysis gasoline as an independent process, liquefied petroleum gas (LPG) can be further produced together with aromatic components. In particular, in a region such as Korea where most of liquefied petroleum gas depends on imports, if liquefied petroleum gas is produced as a by-product, a considerable portion of imported LPG can be substituted.
US Pat. No. 4,058,454 US Pat. No. 3,729,409 US Pat. No. 2,849,290 US Pat. No. 3,950,241 US Pat. No. 5,865,986 US Pat. No. 6,001,241

  However, there are many limitations to commercializing the concept. In particular, coke deposition on the catalyst can occur due to side reactions, thus shortening the life of the catalyst. Therefore, a technology that complements this problem is required. Coke deposition can be suppressed by supporting a metal component having strong hydrogenation activity on the zeolite catalyst, such as a metal of Group VIII of the periodic table. However, the strong hydrogenation activity of the metal component induces a side reaction that converts the aromatic compound to a non-aromatic compound by a hydrogenation reaction. Therefore, it is necessary to adjust the hydrogenation effect by the metal component. In US Pat. No. 5,865,986, the content of adjusting metal activity using a sulfur compound is included. This has led to research on methods for regulating the hydrogenation activity of Group VIII metals by introducing another metal component.

  As a result of intensive studies, the inventors of the present invention are methods for producing aromatic hydrocarbons and LPG from a hydrocarbon mixture derived according to the present invention, in which hydrocarbon feedstocks such as reformed oil and pyrolysis gasoline are added. High purity by converting into liquid phase aromatic hydrocarbon mixture and gas phase non-aromatic hydrocarbon mixture in the presence of zeolite series catalyst with platinum and bismuth without going through a typical solvent extraction process Has been developed to simultaneously obtain a mixture of aromatic hydrocarbons and liquefied petroleum gas (LPG).

  Accordingly, an object of the present invention is to provide a method for obtaining a high-purity aromatic hydrocarbon mixture and LPG from a hydrocarbon feedstock by replacing the solvent extraction step with a reaction step.

  Another object of the present invention is to provide a method for converting a non-aromatic hydrocarbon compound in a hydrocarbon feedstock into a gas phase product containing a large amount of LPG by hydrocracking reaction in the presence of a catalyst. is there.

  According to an embodiment of the present invention, in order to achieve the above and other objects, a method for producing an aromatic hydrocarbon and LPG from a hydrocarbon mixture is provided, the method comprising the following steps: (a) a hydrocarbon Introducing a feedstock mixture and hydrogen into at least one reaction zone; (b) converting the hydrocarbon feedstock mixture into a non-aromatic hydrocarbon compound rich in LPG by (i) hydrocracking reaction in the presence of a catalyst; And (ii) conversion into an aromatic hydrocarbon compound rich in benzene, toluene and xylene (BTX) by a dealkylation / transalkylation reaction within the reaction zone, and (c) gas-liquid separation and distillation Respectively recovering LPG and aromatic hydrocarbon compound from the reaction product of step (b), wherein the catalyst comprises 0.01 Produced by supporting 0.5 parts by mass of platinum (Pt) and 0.01 to 3.0 parts by mass of bismuth (Bi) on 100 parts by mass of a mixed support, 10 to 95% by weight zeolite selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite and combinations thereof, and 5 to 90% by weight inorganic, wherein the molar ratio of alumina is 200 or less It is a process which is a mixed support containing a binder.

  The step of the present invention may further include separating the aromatic hydrocarbon compound recovered in the step (c) into benzene, toluene, xylene and an aromatic compound having 9 or more carbon atoms.

Preferably, in said step (a), the molar ratio of hydrogen and hydrocarbon feedstock mixture is 0.5 to 10 and the space velocity of the hydrocarbon feedstock mixture introduced into the reaction zone is 0.5 To 10 hours ^-1 .

  Preferably step (b) is carried out at 250 to 600 ° C. and under a pressure of 5 to 50 atmospheres.

  The hydrocarbon feedstock mixture may be selected from the group consisting of reformed oil, pyrolysis gasoline, aromatic compounds containing 9 or more carbon atoms including mixtures, naphtha, and mixtures thereof.

Furthermore, the mixed support preferably has an average pore diameter of 50 to 200 mm, a pore volume of 0.1 to 1 cm ³ , a specific surface area of 200 to 400 m ² / g, and an apparent bulk density of 0.4 to. 1. 0 g / cm ³ .

    The inorganic binder may be selected from the group consisting of bentonite, kaolin, clinoptilolite, montmorillonite, γ-alumina, silica, silica-alumina, and mixtures thereof.

  The catalyst is made by mixing zeolite, inorganic binder, platinum and bismuth; and shaping the mixture.

According to one embodiment of the invention, the catalyst mixes the zeolite and the inorganic binder, then shapes the mixture, supports the bismuth on the shaped mixture support; and on the bismuth-supported mixed support. Can be produced by supporting platinum.

  According to another embodiment of the present invention, the catalyst is prepared by mixing a zeolite and an inorganic binder; supporting a mixture of platinum and bismuth on a mixed support; and forming a supported mixed support. Can be done.

  According to a further embodiment of the invention, the catalyst supports platinum on the zeolite; mixes the platinum supported zeolite and the inorganic binder, then shapes the mixture; and the platinum supported mixed support. It can be produced by supporting bismuth on top.

  According to yet a further embodiment of the present invention, the catalyst mixes the zeolite and the inorganic binder, and then further supports either platinum or bismuth on the mixed support to form a mixed support; and mixing It can be produced by supporting other metal not supported in the previous step on the support.

According to another embodiment of the present invention, there is provided a process for producing aromatic hydrocarbons and LPG from a hydrocarbon mixture, the process comprising: (a) at least one reaction zone of a hydrocarbon feedstock mixture and hydrogen. (B) the hydrocarbon feedstock mixture is converted to a non-aromatic hydrocarbon compound rich in LPG by hydrocracking reaction in the presence of a catalyst, and (ii) dehydrated in the reaction zone. An alkylation / transalkylation reaction converts BTX rich aromatic hydrocarbon compounds, and (c) the reaction product of step (b) is an overhead stream containing hydrogen, methane, ethane and LPG. And a bottom stream containing aromatic hydrocarbon compounds and the remaining hydrogen and non-aromatic hydrocarbon compounds separated by gas-liquid separation And (d) recovering LPG from the top stream and (e) recovering aromatic hydrocarbon compounds from the bottom stream, wherein the catalyst comprises 0.01 to 0.5 parts by weight of platinum ( Pt) and 0.01 to 3.0 parts by weight of bismuth (Bi) supported on 100 parts by weight of a mixed support, wherein the silica / alumina molar ratio is 200 or less, A mixed support comprising 10 to 95% by weight zeolite selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite and combinations thereof, and 5 to 90% by weight inorganic binder.

  According to another embodiment of the present invention, there is provided a process for producing aromatic hydrocarbons and LPG from a hydrocarbon mixture, the step comprising: (a) at least one reaction zone of a hydrocarbon feedstock mixture and hydrogen. (B) the hydrocarbon feedstock mixture is converted to a non-aromatic hydrocarbon compound rich in LPG by (i) hydrocracking reaction in the presence of a catalyst, and (ii) degassed in the reaction zone. An alkylation / transalkylation reaction converts to an aromatic hydrocarbon compound rich in BTX; (c) the reaction product of step (b) is converted to a first top stream comprising hydrogen, methane, ethane and LPG; Separating the residual hydrogen and non-aromatic hydrocarbon compounds into a bottom stream containing aromatic hydrocarbon compounds by gas-liquid separation, (d) recovering LPG from the top stream; and (e) by distillation Separating said first bottom stream into (i) a second top stream comprising residual hydrogen and non-aromatic hydrocarbon compounds and (ii) a second bottom stream comprising aromatic hydrocarbon compounds; f) recovering LPG from the second top stream and recovering aromatic hydrocarbon compounds from the second bottom stream, wherein the catalyst comprises 0.01 to 0.5 parts by weight of platinum (Pt) and 0.01 to 3.0 parts by mass of bismuth (Bi) supported on 100 parts by mass of a mixed support, wherein the mixed support has a silica / alumina molar ratio of 200 or Less than, a mixture comprising 10 to 95% by weight zeolite selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite and combinations thereof, and 5 to 90% by weight inorganic binder It is a process which is a joint support.

Advantageous Effects As noted above, the present invention provides a non-aromatic carbonization comprising a high purity aromatic hydrocarbon mixture and LPG as a by-product from a hydrocarbon feedstock mixture using a platinum / bismuth supported zeolitic catalyst. A method for obtaining a hydrogen compound is provided. According to the method of the present invention, only a distillation column is used without the need for an additional solvent extraction device, whereby it can be easily separated from each non-aromatic component and aromatic component. Furthermore, a non-aromatic compound with a low utility value in the hydrocarbon feedstock mixture can be converted to LPG to show economic advantages. In particular, aromatic compounds that are high value-added substances can be obtained with high purity.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating a process for producing aromatic hydrocarbons and liquefied petroleum gas (LPG) from a hydrocarbon feedstock mixture according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically with reference to the accompanying drawings.
The present invention relates to a process for producing an aromatic hydrocarbon mixture and LPG from a hydrocarbon feedstock mixture.

Typical examples of the hydrocarbon feedstock mixture include catalytic reformed oil, pyrolysis gasoline, a mixture containing an aromatic compound having 9 or more carbon atoms, naphtha, and a mixture thereof. When the aromatic compound is mainly recovered, a feedstock oil having a high aromatic component content, such as catalytically modified oil or pyrolysis gasoline, is preferably used. Furthermore, when LPG is mainly produced, a raw material oil having a high content of non-aromatic components, such as naphtha, is preferably used.

  In the presence of the catalyst according to the present invention, the hydrogenolysis reaction of the non-aromatic hydrocarbon compound and the dealkylation reaction and transalkylation reaction of the aromatic compound are carried out simultaneously. These reactions yield major aromatic intermediates used in the petrochemical industry such as benzene, toluene, xylene, and non-aromatic compounds such as LPG as by-products.

  Among these reactions, a reaction in which a liquid non-aromatic compound is converted into a gas phase substance by a hydrogenolysis reaction is particularly important. The hydrocracking reaction eliminates the need for a solvent extraction step for the aromatic hydrocarbon compound.

  Aromatic dealkylation and transalkylation reactions improve the properties of aromatic compounds. That is, an aromatic compound having 9 or more carbon atoms, which is mainly used as fuel oil, can be converted into benzene, toluene, xylene or the like by a dealkylation reaction to improve its characteristics. Transalkylation reactions between aromatic compounds also improve the properties of aromatic hydrocarbon mixtures. For example, when benzene is reacted with an aromatic compound having 9 or more carbon atoms, toluene and xylene can be obtained.

  These reactions described above can be introduced by using a zeolite catalyst having a strong acid action. The zeolite catalyst constitutes pores having a diameter (about 5 to 7 mm) suitable for passage and reaction of hydrocarbon molecules having 5 to 12 carbon atoms having a boiling point of 30 to 250 ° C. Further, the catalyst is used in the form of a mixed support obtained by mixing at least one selected from the group consisting of mordenite, β-type zeolite and ZSM-5-type zeolite with an inorganic binder.

In the hydrogenolysis reaction and dealkylation reaction, olefins such as ethylene and propylene are produced. In this case, it is necessary to quickly hydrogenate such olefins. This is because the generated olefin component is again alkylated to an aromatic compound, thereby deteriorating the properties of the aromatic component and forming a liquid phase non-aromatic compound by a polymerization reaction, or deactivation of the catalyst. This is to promote the production of coke that causes crystallization. Therefore, a metal with a strong hydrogenation action should be mixed on the zeolite. Generally, when a strong hydrogenation action is required, nickel (Ni), palladium (Pd), platinum (Pt), etc. which are metals of Group VIII of the periodic table are used. Among the active metals mentioned above, platinum has the strongest hydrogenating action. In the present invention, in order to suppress the side reaction, platinum is mixed into the catalyst as a very suitable metal.

  Platinum, the active metal component with the strongest hydrogenation action, achieves the rapid hydrogenation of olefins required in the present invention, improving the reaction product properties and increasing the catalyst deactivation rate. It is advantageously used to reduce. However, platinum induces side reactions such as conversion of aromatic compounds to naphthenic compounds. That is, in addition to the hydrogenolysis reaction, dealkylation reaction and transalkylation reaction, the aromatic compound is converted to a naphthenic hydrocarbon by the hydrogenation reaction, and the naphthenic compound is further hydrocracked, and this Is converted to gas phase paraffinic hydrocarbons. The reaction is not preferable in terms of reducing the residual amount of the aromatic compound.

  Therefore, the activity of platinum must be adjusted appropriately to initiate a selective hydrogenation reaction on olefins. Therefore, in the present invention, bismuth (Bi) is used as the second metal component and gives selective hydrogenation to platinum.

  Bismuth introduced as the second metal component and regulating the activity of platinum interacts with platinum and suppresses side reactions caused by the strong hydrogenation action of platinum. In particular, when bismuth (Bi) is introduced as the second metal component, the platinum activity is suppressed more effectively due to stronger interaction with platinum compared to the case where tin (Sn) or lead (Pb) is introduced. And thus more effectively control the action of platinum as the active metal. Thus, bismuth can enhance the selective hydrogenation of platinum and therefore suppress side reactions due to excessive hydrogenation. In addition, bismuth causes strong interaction with platinum as the active metal component, while minimizing the negative impact on the acid action of the mixed support, thereby reducing the hydrocracking reaction of non-aromatic compounds, and aromatic compounds The dealkylation and transalkylation reactions of can be efficiently guided. In particular, the hydrocracking reaction performance of non-aromatic components is improved. As a result, the yield of LPG is increased and a higher-purity aromatic hydrocarbon compound can be produced.

  Mordenite, β-type zeolite and ZSM-5-type zeolite are produced in the form of sodium salt during the initial synthesis and can be ion-exchanged with ammonium chloride or ammonium nitrate to obtain the ammonium form. The ammonium form zeolite is calcined, whereby a hydrogen form zeolite can be obtained. In the present invention, mordenite, β-type zeolite and ZSM-5-type zeolite, each in ammonium form or hydrogen form, can be used. The mordenite, β-type zeolite or ZSM-5-type zeolite used in the present invention should have a silica / alumina molar ratio of 200 or less. If the silica / alumina molar ratio is greater than 200, the reaction activity decreases and the temperature required for the reaction increases significantly to an undesirable degree.

  The zeolite is used in the form of a mixed support mixed with at least one inorganic binder. As such, the inorganic binder includes at least one selected from the group consisting of bentonite, kaolin, clinoptilolite, montmorillonite, γ-alumina, silica, and silica-alumina. Preferably, at least one selected from the group consisting of amorphous inorganic oxides of γ-alumina, silica and silica-alumina is used, and more preferably γ-alumina and / or silica is used.

  When the inorganic binder is combined with zeolite, 10 to 95% by mass of zeolite and 5 to 90% by mass of inorganic binder are mixed and formed into a cylinder or a sphere.

  As such, if the zeolite content is less than 10% by mass, the required reaction temperature will rise drastically. On the other hand, when the content exceeds 95% by mass, the mechanical strength of the catalyst becomes poor.

  When the mixed support is formed into a cylinder, it is preferable to form the mixed support so that the diameter is 1 to 3 mm and the length is 5 to 30 mm. Furthermore, when the mixed support is formed into a spherical shape, it is preferable to form the mixed support so that the diameter is 1 to 5 mm.

The mixed support containing the zeolite and the inorganic binder thus formed preferably has an average pore diameter of 50 to 200 mm, a pore volume of 0.1 to 1 cm ³ , a specific surface area of 200 to 400 m ² / g, And an apparent bulk density of 0.4 to 1.0 g / cm ³ .

  In the present invention, the zeolite and inorganic binder can be mixed and molded, and then platinum / bismuth can be supported thereon, thus producing the final catalyst. Alternatively, the metal component can be supported on the zeolite and then mixed with an inorganic binder to form the final catalyst.

  Thus, when a metal is supported before or after the molding process, the order of introduction of the two supported metals is not a problem, either one of the metals can be introduced first, or two Metal can be introduced simultaneously. Furthermore, during the shaping of the support, the support can be mixed and shaped with the mixture comprising the two metals. Furthermore, during molding, the support and any one of the two metals can be mixed and molded, and then other metals can be supported thereon, thus producing the final catalyst. obtain.

  Platinum which is an active component of the catalyst is preferably supported in an amount of 0.01 to 0.5 parts by mass with respect to 100 parts by mass of the mixed support including zeolite and an inorganic binder. In this case, if the mass of platinum is less than 0.01 parts by mass with respect to 100 parts by mass of the mixed support, the rate of the hydrogenolysis reaction and dealkylation reaction is decreased, and the reaction temperature is thereby increased I have to let it. The rate of catalyst deactivation also increases to an undesirable extent. On the other hand, if the mass of platinum exceeds 0.5 parts by mass with respect to 100 parts by mass of the mixed support, the hydrogenolysis reaction occurs actively, and the aromatic compound is greatly converted into a naphthenic compound. Converted.

  As a method for supporting platinum, ion exchange, impregnation, and physical mixing methods can be applied. Such a support process can be easily guided by those having ordinary knowledge in the art. When platinum is supported by ion exchange, an aqueous solution of ammonium chloroplatinate or dinitrodiaminoplatinum is used as a precursor. When platinum is introduced by impregnation, an aqueous solution of chloroplatinic acid or ammonium chloroplatinate is used as a precursor. In addition, all aqueous solutions of the precursors can be used during physical mixing.

  In the reaction of the present invention, the bismuth used as a metal component supported on the mixed support together with platinum is preferably 0.01 to 3.0 parts by mass with respect to 100 parts by mass of the mixed support including zeolite and an inorganic binder. Introduced in As such, when the amount of bismuth used exceeds 3.0 parts by weight with respect to 100 parts by weight of the mixed support, the action of platinum is extremely suppressed, and thus the reactivity is reduced and the catalyst is reduced. The deactivation rate of the increases undesirably. On the other hand, if the amount is less than 0.01 parts by mass, the strong hydrogenation action of platinum cannot be appropriately adjusted, resulting in an increase in side reactions.

  Bismuth is preferably supported on the mixing support by an impregnation process or a mixing process. Examples of the bismuth precursor include bismuth (III) chloride, bismuth oxychloride (III), bismuth nitrate and bismuth acetate.

  In the present invention, after the platinum / bismuth is supported on the mixed support, the supported mixed support is preferably dried at 60 to 200 ° C. for 30 minutes to 2 hours in an air atmosphere. The dried catalyst is preferably calcined at 300 to 600 ° C. for 1 to 12 hours in an air or nitrogen atmosphere.

  As mentioned above, when a metal component such as platinum / bismuth is supported on a mixed support comprising a zeolite and an inorganic binder, the order of introduction is irrelevant and can be introduced sequentially or simultaneously. obtain. As such, these metals are preferably present in a bonded state. In particular, platinum is an excellent catalyst when it is present in a space from bismuth by a form bound to bismuth or close enough to electrically and chemically affect each other rather than being present independently in the catalyst. Expect performance.

That is, when platinum is present alone, the aforementioned side reaction can occur due to the high hydrogenation activity of platinum. However, when bismuth binds to platinum or is at a sufficiently close distance, platinum exhibits selective hydrogenation due to metal-to-metal interactions that can be explained by ensemble or ligand effects, and is therefore optimal. The reaction performance can be expected.

  FIG. 1 outlines a process for producing aromatic hydrocarbons and LPG from a hydrocarbon feedstock mixture according to the present invention.

  As shown in the figure, the catalyst functions to cause dealkylation, transalkylation and hydrocracking reactions of the hydrocarbon feedstock mixture in at least one reactor in the reaction zone. The feedstock containing aromatic and non-aromatic components is mixed with hydrogen before being introduced into the reactor.

  Under the present circumstances, the molar ratio of hydrogen and feedstock is 0.5-10. When the molar ratio is less than 0.5, the deactivation of the catalyst proceeds rapidly. On the other hand, when the molar ratio exceeds 10, the aromatic component is converted into a saturated cyclic hydrocarbon, and thus the aromatic yield decreases.

A hydrocarbon feedstock stream 111 introduced into the process is mixed with a hydrogen stream 121 and a high purity hydrogen stream 112. Hydrogen / feed oil 114 is introduced into reactor 103 at a space velocity per hour (WHSV) of 0.5 to 10 h ⁻¹ and reacts at 250 to 600 ° C. under pressure conditions of 5 to 50 atmospheres.

  In this case, a separate heater 102 is installed to raise the temperature of the hydrogen / feed oil mixture to the reaction temperature. Before being introduced into the heater 102, the hydrogen / raw oil is heat-exchanged with the reaction product stream 115 that is discharged from the reactor 103 and circulated to the heat exchanger 101, and is then heated in a state 113 where the Introduced in.

  In the reactor containing the hydrogen / feed oil 114, the dealkylation reaction of the aromatic component, and the transalkylation reaction and the hydrocracking reaction of the non-aromatic component are performed in the presence of a catalyst under the above reaction conditions.

  After the reaction is complete, product 115 is present in the gas phase product at a relatively high temperature and circulates to heat exchanger 101 before it is introduced into gas-liquid separator 104, releasing heat to the hydrogen / feed oil. And then passes through the first cooler 105.

  The product stream 117 that has passed through the first cooler 105 is introduced into the gas-liquid separator 104 at about 30 to 50 ° C. and separated into a gas phase component 119 and a liquid phase component 118. The gas phase component 119 is discharged from the gas-liquid separator 104 as a first overhead stream, and the liquid phase component 118 is discharged as a first bottom stream.

  In this case, the gas phase component 119 includes about 60 to 75 mol% hydrogen and 25 to 40 mol% hydrocarbon component, and the hydrocarbon component includes low carbon methane, ethane, LPG, and the like.

  The hydrogen component is compressed by a compressor 106, combined with high purity hydrogen 112 for adjusting the hydrogen purity, and then introduced into the reaction zone together with the feedstock 111. Further, the liquid phase component 118 mainly comprises an aromatic component and a small amount of residual hydrogen and light non-aromatic components.

  Accordingly, the liquid phase component 118 is again subjected to a separation and purification step, and due to the difference in boiling point in the first distillation column 107, the second upper end stream 122 containing residual hydrogen and non-aromatic components, and a purity of 99% or more. Is separated into a second bottom stream 128 containing the following aromatic components.

  The second bottom stream 128 is recovered and then separated into benzene, toluene, xylene, aromatic compounds having 9 or more carbon atoms, etc. in a second distillation column.

  On the other hand, the second upper end stream 122 is cooled in the second cooler 108, and then, using the gas-liquid separator 109, the third upper end stream as a gas phase mixture containing residual hydrogen, methane and ethane. 129 and can thus be used as fuel. The third bottom stream 126 in the liquid phase circulates again into the distillation column 107, a portion of which is recovered as stream 127 containing pentane, hexane, LPG components, and the like. The component circulating in the distillation tower undergoes a separation step together with the first bottom stream.

  As a result, the aromatic mixture can be separated with a purity of 99% or higher, and the LPG component is obtained as stream 120 with hydrogen removed from the first top stream 119, and stream 127. As such, stream 120 includes an amount corresponding to about 70-90% of the total LPG component.

Aspects of the Invention The present invention can be clearly understood based on the examples described below, but should not be construed as limiting the invention.

Comparative Example 1
A mixed support containing a ZSM-5 type zeolite having a silica / alumina molar ratio of 30 and γ-alumina as a binder is mixed with an aqueous H ₂ PtCl ₆ solution and an aqueous SnCl ₂ solution to remove platinum and tin. The content of ZSM-5 type zeolite was adjusted to 75% by mass. Platinum and tin were supported in an amount of 0.03 parts by mass and 0.5 parts by mass, respectively, with respect to 100 parts by mass of the total amount of the ZSM-5 type zeolite and binder. The mixed support thus supported was molded to have a diameter of 2 mm and a length of 10 mm, dried at 120 ° C. for 3 hours, and then calcined at 500 ° C. for 3 hours to produce a catalyst. The hydrocarbon mixture was reacted using the catalyst thus produced. The reaction conditions and the reaction results are shown in Table 1 below.

Example 1
A mixed support containing a ZSM-5 type zeolite having a silica / alumina molar ratio of 30 and γ-alumina as a binder is mixed with an aqueous H ₂ PtCl ₆ solution and an aqueous Bi (NO ₃ ) ₃ solution to remove platinum and bismuth. The content of ZSM-5 type zeolite in the support was 75% by mass. Platinum and bismuth were supported in an amount of 0.03 parts by mass and 0.5 parts by mass, respectively, with respect to 100 parts by mass of the total amount of ZSM-5 type zeolite and binder. The mixed support thus supported was molded to have a diameter of 2 mm and a length of 10 mm, dried at 120 ° C. for 3 hours, and calcined at 500 ° C. for 3 hours to produce a catalyst. The hydrocarbon mixture was reacted using the catalyst thus produced. The reaction conditions and the reaction results are shown in Table 1 below.

Example 2
A mixed support containing a ZSM-5 type zeolite having a silica / alumina molar ratio of 30 and γ-alumina as a binder is mixed with an aqueous H ₂ PtCl ₆ solution and an aqueous BiCl ₃ solution to remove platinum and bismuth. The content of ZSM-5 type zeolite was adjusted to 75% by mass. Platinum and bismuth were supported in an amount of 0.03 parts by mass and 0.25 parts by mass, respectively, with respect to 100 parts by mass of the total amount of the ZSM-5 type zeolite and binder. The mixed support thus supported was molded to have a diameter of 2 mm and a length of 10 mm, dried at 120 ° C. for 3 hours, and then calcined at 500 ° C. for 3 hours,
A catalyst was prepared. The hydrocarbon mixture was reacted using the catalyst thus produced. The reaction conditions and the reaction results are shown in Table 1 below.

Example 3
A mixed support comprising a ZSM-5 type zeolite having a silica / alumina molar ratio of 30 and a mordenite having a silica / alumina molar ratio of 20 and γ-alumina as a binder together with an aqueous H ₂ PtCl ₆ solution and an aqueous BiCl ₃ solution. By mixing, the contents of the ZSM-5 type zeolite and mordenite in the support excluding platinum and bismuth were 50% by mass and 25% by mass, respectively. Platinum and bismuth were supported in an amount of 0.03 parts by mass and 0.25 parts by mass, respectively, with respect to 100 parts by mass of the total amount of the ZSM-5 type zeolite, mordenite and binder. The mixed support thus supported was molded to have a diameter of 2 mm and a length of 10 mm, dried at 120 ° C. for 3 hours, and then calcined at 500 ° C. for 3 hours to produce a catalyst. The hydrocarbon mixture was reacted using the catalyst thus produced. The reaction conditions and the reaction results are shown in Table 1 below.

Example 4
A mixed support containing β-type zeolite having a silica / alumina molar ratio of 25 and γ-alumina as a binder is mixed with an aqueous H ₂ PtCl ₆ solution and an aqueous BiCl ₃ solution,
The content of β-type zeolite in the support excluding platinum and bismuth was 75% by mass. Platinum and bismuth were supported in amounts of 0.03 parts by mass and 0.25 parts by mass, respectively, with respect to 100 parts by mass of the total amount of β-type zeolite and binder. The mixed support thus supported was molded to have a diameter of 2 mm and a length of 10 mm, dried at 120 ° C. for 3 hours, and then calcined at 500 ° C. for 3 hours to produce a catalyst. The hydrocarbon mixture was reacted using the catalyst thus produced. The reaction conditions and the reaction results are shown in Table 1 below.

As is clear from Table 1, from the results of mass% of the non-aromatic compound having 5 or more carbon atoms in the product, compared with Comparative Example 1 using the process of the prior art, the process according to the present invention was performed. It can be seen that the hydrocracking reaction performance of the non-aromatic component is greatly improved. By improving the performance of such hydrocracking reaction, non-aromatic components and aromatic components can be more easily separated from each other without additional solvent extraction equipment. In addition, the aromatic hydrocarbon compound can be obtained with higher purity. Furthermore, according to the present invention, the amount of LPG can be increased by conversion of a non-aromatic hydrocarbon compound.

  As described above, the present invention uses a platinum / bismuth supported zeolitic catalyst, from a hydrocarbon feedstock mixture to a non-aromatic carbon containing high purity aromatic hydrocarbon mixture and LPG as a byproduct. A method for obtaining a hydrogen compound is provided. According to the method of the present invention, the non-aromatic component and the aromatic component can be easily separated from each other by using only a distillation column without installing an additional solvent extraction device. Further, the non-aromatic compound having a low utility value in the hydrocarbon feedstock mixture can be converted to LPG to improve the economics of the process. In particular, an aromatic compound that is a high value-added substance can be obtained with high purity.

  Although preferred embodiments of the present invention have been disclosed above, those skilled in the art will recognize that various modifications and additions can be made without departing from the spirit and scope of the present invention as disclosed in the appended claims. Or it will be understood that substitutions may be added.

FIG. 1 is a diagram illustrating a process for producing aromatic hydrocarbons and liquefied petroleum gas (LPG) from a hydrocarbon feedstock mixture according to the present invention.

Claims (16)

Introducing (a) a hydrocarbon feedstock mixture and hydrogen into at least one reaction zone;
(B) converting the hydrocarbon feedstock mixture into a non-aromatic hydrocarbon compound rich in LPG by a hydrocracking reaction in the presence of a catalyst, and (ii) dealkylating / Transalkylation reaction converts benzene, toluene and xylene (BTX) rich aromatic hydrocarbon compounds; and (c) from the reaction product of step (b) by gas-liquid separation and distillation, LPG and aromatics Collecting each hydrocarbon compound,
Here, the catalyst supports 0.01 to 0.5 parts by mass of platinum (Pt) and 0.01 to 3.0 parts by mass of bismuth (Bi) on 100 parts by mass of a mixed support. The prepared mixed support has a silica / alumina molar ratio of 200 or less, and is selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite, and combinations thereof. And a mixed support comprising 5 to 90% by weight of an inorganic binder.
A process for producing aromatic hydrocarbons and liquefied petroleum gas (LPG) from a hydrocarbon mixture.   The method according to claim 1, further comprising separating the aromatic hydrocarbon compound recovered in the step (c) into benzene, toluene, xylene and an aromatic compound having 9 or more carbon atoms. Step a molar ratio of 0.5 to 10 hydrogen and hydrocarbon feedstock mixture in (a), and space velocity of the hydrocarbon feedstock mixture introduced into the reaction zone, 0.5 to 10 hours ^{- 1,} the method of claim 1.   The process according to claim 1, wherein step (b) is carried out at 250 to 600 ° C under a pressure of 5 to 50 atmospheres.   The method according to claim 1, wherein the hydrocarbon feedstock mixture is selected from the group consisting of reformed oil, pyrolysis gasoline, a mixture containing the above aromatic compound having 9 or more carbon atoms, naphtha, and mixtures thereof. . The mixed support has an average pore diameter of 50 to 200 mm, a pore volume of 0.1 to 1 cm ³ , a specific surface area of 200 to 400 m ² / g, and an apparent bulk density of 0.4 to 1.0 g / The method of claim 1 having cm ³ .   The method of claim 1, wherein the inorganic binder is selected from the group consisting of bentonite, kaolin, clinoptilolite, montmorillonite, γ-alumina, silica, silica-alumina, and combinations thereof.   The process according to claim 1, wherein the catalyst is produced by mixing zeolite, inorganic binder, platinum and bismuth; and shaping the mixture.   The catalyst is prepared by mixing a zeolite and an inorganic binder, then forming a mixture, supporting bismuth on a forming mixture support; and supporting platinum on a bismuth supported support. The method of claim 1. The process of claim 1, wherein the catalyst is made by mixing a zeolite and an inorganic binder; supporting a mixture of platinum and bismuth on a mixed support; and molding a supported mixed support.   The catalyst is produced by supporting platinum on a zeolite; mixing the platinum supported zeolite and an inorganic binder, then shaping the mixture; and supporting bismuth on the platinum supported mixed support. The method according to claim 1.   The catalyst mixes the zeolite and inorganic binder and then further supports either platinum or bismuth on the mixed support to form the mixed support; and is not supported on the mixed support in the previous step. The method according to claim 1, wherein the method is produced by supporting another metal. Introducing (a) a hydrocarbon feedstock mixture and hydrogen into at least one reaction zone;
(B) converting the hydrocarbon feedstock mixture to a non-aromatic hydrocarbon compound rich in LPG by a hydrocracking reaction in the presence of a catalyst, and (ii) dealkylating / trans in said reaction zone Conversion to an aromatic hydrocarbon compound rich in BTX by an alkylation reaction;
(C) converting the reaction product of step (b) into an overhead stream comprising hydrogen, methane, ethane and LPG and a bottom stream comprising an aromatic hydrocarbon compound, and the residual hydrogen and Separating non-aromatic hydrocarbon compounds by gas-liquid separation;
(D) recovering LPG from the top stream; and (e) recovering aromatic hydrocarbon compounds from the bottom stream;
Here, the catalyst supports 0.01 to 0.5 parts by mass of platinum (Pt) and 0.01 to 3.0 parts by mass of bismuth (Bi) on 100 parts by mass of a mixed support. The prepared mixed support has a silica / alumina molar ratio of 200 or less, and is selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite, and combinations thereof. And a mixed support comprising 5 to 90% by weight of an inorganic binder,
A process for producing aromatic hydrocarbons and LPG from hydrocarbon mixtures.   The method according to claim 13, further comprising separating the aromatic hydrocarbon compound recovered in the step (e) into benzene, toluene, xylene and an aromatic compound having 9 or more carbon atoms. Introducing (a) a hydrocarbon feedstock mixture and hydrogen into at least one reaction zone;
(B) converting the hydrocarbon feedstock mixture to a non-aromatic hydrocarbon compound rich in LPG by a hydrocracking reaction in the presence of a catalyst, and (ii) dealkylating / trans in said reaction zone Conversion to an aromatic hydrocarbon compound rich in BTX by an alkylation reaction;
(C) the reaction product of step (b) is transferred to a first top stream comprising hydrogen, methane, ethane and LPG and a bottom stream comprising aromatic hydrocarbon compounds, and the remaining hydrogen and non-aromatic hydrocarbons Separating the compounds by gas-liquid separation;
(D) recovering LPG from the first top stream; and (e) distilling said first bottom stream into (i) a second top stream comprising residual hydrogen and non-aromatic hydrocarbon compounds and ( ii) separating into a second bottom stream containing aromatic hydrocarbon compounds, and (f) recovering LPG from the second top stream and recovering aromatic hydrocarbon compounds from the second bottom stream. Including
Here, the catalyst supports 0.01 to 0.5 parts by mass of platinum (Pt) and 0.01 to 3.0 parts by mass of bismuth (Bi) on 100 parts by mass of a mixed support. The prepared mixed support has a silica / alumina molar ratio of 200 or less, and is selected from the group consisting of mordenite, β-zeolite, ZSM-5 zeolite, and combinations thereof. And a mixed support comprising 5 to 90% by weight of an inorganic binder,
A process for producing aromatic hydrocarbons and LPG from hydrocarbon mixtures.   The method according to claim 15, further comprising separating the aromatic hydrocarbon compound recovered in the step (f) into benzene, toluene, xylene and an aromatic compound having 9 or more carbon atoms, respectively.

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